package org.jenijo.querydroid;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.Reader;
import java.io.StringWriter;
import java.io.UnsupportedEncodingException;
import java.io.Writer;
import java.net.URLEncoder;
import java.util.ArrayList;

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.HttpClient;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.client.methods.HttpUriRequest;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.message.BasicNameValuePair;
import org.apache.http.protocol.HTTP;

import android.content.res.Resources;

public class RestClient {
	private ArrayList<NameValuePair>	params;
	private ArrayList<NameValuePair>	headers;
	private String						url;
	private int							responseCode;
	private String						message;
	private String						response;
	
	public RestClient(String url) {
		this.url = url;
		params = new ArrayList<NameValuePair>();
		headers = new ArrayList<NameValuePair>();
		message = response = null;
	}
	
	public String getResponse() {
		return response;
	}
	
	public String getErrorMessage() {
		return message;
	}
	
	public int getResponseCode() {
		return responseCode;
	}
	
	public RestClient addParam(String name, String value) {
		params.add(new BasicNameValuePair(name, value));
		return this;
	}
	
	public RestClient addHeader(String name, String value) {
		headers.add(new BasicNameValuePair(name, value));
		return this;
	}
	
	public RestClient execute(RequestMethod method) throws UnsupportedEncodingException {
		switch(method) {
			case GET: {
				// add parameters
				String combinedParams = "";
				if(!params.isEmpty()){
					combinedParams += "?";
					for(NameValuePair p : params){
						String paramString = p.getName() + "="
								+ URLEncoder.encode(p.getValue(), "UTF-8");
						if(combinedParams.length() > 1){
							combinedParams += "&" + paramString;
						}else{
							combinedParams += paramString;
						}
					}
				}
				
				HttpGet request = new HttpGet(url + combinedParams);
				
				// add headers
				for(NameValuePair h : headers){
					request.addHeader(h.getName(), h.getValue());
				}
				
				executeRequest(request);
				break;
			}
			case POST: {
				HttpPost request = new HttpPost(url);
				
				// add headers
				for(NameValuePair h : headers){
					request.addHeader(h.getName(), h.getValue());
				}
				
				if(!params.isEmpty()){
					request.setEntity(new UrlEncodedFormEntity(params, HTTP.UTF_8));
				}
				
				executeRequest(request);
				break;
			}
		}
		return this;
	}
	
	private void executeRequest(HttpUriRequest request) {
		HttpClient client = new DefaultHttpClient();
		
		HttpResponse httpResponse;
		
		try{
			httpResponse = client.execute(request);
			responseCode = httpResponse.getStatusLine().getStatusCode();
			message = httpResponse.getStatusLine().getReasonPhrase();
			
			HttpEntity entity = httpResponse.getEntity();
			
			if(entity != null){
				
				InputStream instream = entity.getContent();
				response = convertStreamToString(instream);
			}
		}catch (ClientProtocolException e){
			client.getConnectionManager().shutdown();
			message = Resources.getSystem().getString(R.string.httpProtocolError)+" : " + e.getLocalizedMessage() + " !";
		}catch (IOException e){
			client.getConnectionManager().shutdown();
			message = Resources.getSystem().getString(R.string.connectionError)+" : " + e.getLocalizedMessage() + " !";
		}
	}
	
	private static String convertStreamToString(InputStream is) throws IOException {
		Reader reader = new BufferedReader(new InputStreamReader(is));
		char[] buffer = new char[1024];
		int n;
		Writer writer = new StringWriter();
		
		while((n = reader.read(buffer)) != -1){
			writer.write(buffer, 0, n);
		}
		is.close();
		
		return writer.toString();
	}
}
